Adjustable rotary shutter for motion picture cameras

ABSTRACT

An adjustable shutter for motion picture cameras wherein a disk having a light-admitting aperture rotates with two blades which are movable relative to the disk to thereby overlie varying portions of the aperture. The disk carries a leaf spring having a radially extending slot for a follower pin which extends into arcuate cam slots of the blades and is in frictional engagement with the leaf spring. A shifter is reciprocable in the body of the camera and has two displacing cams one of which can move the follower pin radially outwardly and the other of which can move the follower pin radially inwardly to thereby turn the blades relative to the disk while the disk and the blades rotate. The shifter can be moved by a program wheel to effect gradual changes in the aperture size during the making of exposures with fade-in and/or fade-out effect.

United States Patent [1 1 [111 3,764,199 Neudecker 1 Oct. 9, 1973 ADJUSTABLE ROTARY SHUTTER FOR Primary Examiner-David Schonberg MOTION PICTURE CAMERAS Inventor: Karl Neudecker, Munich, Germany Afga-Gevaert Aktiengesellschaft. Leverkusen. Germany Filed: Mar. 7, 1972 Appl. No.: 232,499

Assignee:

Foreign Application Priority Data Mar. 12, 1971 Germany P 21 11 861.6

References Cited UNITED STATES PATENTS 8/1971 Steiblm, 352/208 2/1925 Warren 352/216 7/1950 Bolsey 352/216 5/1965 Gregory, Jr. et a1 352/208 FOREIGN PATENTS OR APPLICATIONS 4/1965 Austria 352/208 Assistant Examiner-J. P. McGraw Attorney-Michael S. Striker An adjustable shutter for motion picture cameras wherein a disk having a light-admitting aperture rotates with two blades which are movable relative to the disk to thereby overlie varying portions of the ap erture. The disk carries a leaf spring having a radially extending slot for a follower pin which extends into arcuate cam slots of the blades and is in frictional engagement with the leaf spring. A shifter is reciprocable in the body of the camera and has two displacing cams one of which can move the follower pin radially outwardly and the other of which can move the follower pin radially inwardly to thereby turn the blades relative to the disk while the disk and the blades rotate. The shifter can be moved by a program wheel to effect gradual changes in the aperture size during the making of exposures with fade-in and/or fade-out effect.

ABSTRACT 11 Claims, 2 Drawing Figures ADJUSTABLE ROTARY SHUTTER FOR MOTION PICTURE CAMERAS BACKGROUND OF THE INVENTION The present invention relates to shutters in general, and more particularly to improvements in rotary shutters for use in motion picture cameras. Still more particularly, the invention relates to improvements in adjustable rotary shutters wherein the effective size of the light-admitting aperture can be varied while the camera is in use. Such shutters are utilized in motion picture cameras which are provided with fading mechanisms for the making of effect shots known as fade in and fade-out.

An adjustable rotary shutter for use in motion picture cameras normally comprises a rotary disk which has a light-admitting aperture and one or more blades which rotate with the disk and are movable relative to the disk to overlie varying portions of the aperture to thus change the effective size of the aperture and theamount of light which can reach the foremost unexposed film frame. As a rule, the blades are turnable relative to the disk by means of a gear train or by a feed screw or another helical adjuster. A drawback of such adjusting devices is that they occupy a substantial amount of space, particularly as seen in the axial direction of the shutter. Therefore, such adjustable shutters cannot be used in relatively small, and particularly in miniature or pocket-size motion picture cameras.

SUMMARY OF THE INVENTION An object of the invention is to provide a novel and improved adjustable rotary shutter for use in motion picture cameras.

Another object of the invention is to provide a flat adjustable rotary shutter which occupies very little room, particularly as considered in the axial direction of the rotary parts of the shutter.

A further object of the invention is to provide a rotary shutter with novel and improved means for varying the effective size of the light-admitting aperture.

An additional object of the invention is to provide a rotary shutter which can be installed in miniature motion picture cameras and renders it possible to equip such cameras with a fading mechanism.

The invention is embodied in a rotary shutter, particularly in a rotary shutter for use in miniature motion picture cameras, which comprises a preferably diskshaped rotary member having a light-admitting aperture, at least one preferably blade-like second member which is arranged to rotate with the first member, one of the two members being movable relative to the other member to thereby cause the second member to overlie varying portions of the aperture with attendant changes in the effective size of such aperture, and adjusting means for moving the one member relative to the other member. The adjusting means includes follower means which is supported by one of the first and second members, cammeans provided on the other of the first and second members, the follower means being movable relative to the respective member along the cam means to thereby move the movable member, and displacing means which is actuatable to move the follower means relative to the respective member. The follower means is preferably movable in a slot defined by a resilient guide element which is provided on or secured to the disk-shaped first rotary member, and the cam means preferably comprises an arcuate cam slot provided on the second member and receiving a portion of the follower means. The displacing means preferably com prises a first displacing element which can be shifted into the path of movement of the follower means to move the latter substantially radially inwardly toward the axis of rotation of the two members, and a second displacing element which can be moved into the path of the follower means to move the follower means outwardly. The two displacing elements can be mounted on a common shifter which is reciprocable in the body of the camera, either by hand or by a suitable programming device so that the aperture size can be changed in stepwise fashion.

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved shutter itself, however, both as to its construction and its mode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain specific embodiments with reference to the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary transverse vertical sectional view of a motion picture camera which embodies the improved shutter, the section being taken in the direction of arrows as seen from the line l-I of FIG. 2; and

FIG. 2 is a sectional view as seen in the direction of arrows from the line llll of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The drawing illustrates a portion of a miniature or pocket-size motion picture camera which comprises a housing or body having a front wall 2 which supports the lens barrel 3. The optical axis of the picture taking objective is indicated at 4. The body of the camera accommodates a plate-like support or partition I whch is located behind and is shown as being substantially parallel with the front wall 2.

The improved adjustable rotary shutter is mounted in the compartment between the wall 2 and partition I and comprises a disk-shaped rotary member 5 which is secured to a sleeve 9 on a shaft 10 extending in parallelism with the optical axis 4. The disk 5 has a lightadmitting aperture 6 which registers with a stationary light-admitting window 25 located in front of the foremost unexposed film frame during a certain stage of each revolution of the disk 5. The shaft 10 is rotatable in the camera body and the periphery of the disk 5 is provided with an analous of teeth 5a which mesh with the teeth of a pinion 11 mounted on a drive shaft 12. The parts 11 and 12 constitute elements of the drive means for the disk 5, and such drive means further comprises a motor (not shown) which can rotate the drive shaft 12. The shutter further comprises two blades 7 and 8 which are mounted on the sleeve 9 and normally rotate with the disk 5 about the axis of the shaft 10. Still further, the shutter comprises a novel adjusting mechanism which can turn the blades 7 and 8 relative to the disk 5 while the parts 5, 7 and 8 rotate about the axis of th shaft 10 whereby the blades 7 and 8 overlie varying portions of the light-admitting aperture 6 with attendant changes in the effective size of such aperture. Thus, when the effective size of the aperture 6 is reduced, the length of interval during which the aperture 6 admits light to the window 25 during each revolution of the disk 5 is reduced. The arrangement is preferably such that the blades 7 and 8 can completely overlie the aperture 6 to thereby terminate the admission of light to the window 25 and to the film frame behind such window.

The adjusting mechanism which can turn the blades 7 and 8 relative to the disk 5 comprises a guide member 13 which is preferably an elastic element such as a leaf spring. This guide member is mounted on the sleeve 9 and has at its outer end a projection or lug 13a which is bent in the axial direction of the shaft 10 and extends into a cutout 5b of the disk 5. Thus, the guide member 13 shares all angular movements of the disk 5. As best seen in FIG. 1, the guide member 13 is provided with a radially extending guide slot 13b which receives a portion of a pin-shaped follower 14. This follower pin is received in the slot 13!) with at lest some friction so that it must be positively displaced in order to change its distance from the axis of the shaft 10. Portions of the follower pin 14 extend into arcuate cam slots 15 and 16 which are respectively provided in the blades 7 and 8 and are mirror symmetrical with reference to a plane which includes the axes of the shaft 10 and follower pin 14. This is clearly shown in FIG. 1. When the follower pin 14 is caused to move in the slot 13b radially inwardly towards the axis of the shaft 10, it causes simultaneous angular displacements of the blades 7 and 8.

relative to the disk 5 to thereby change the effective size of the aperture 6. For example, the arrangement may be such that the effective size of the aperture 6 is reduced when the follower pin 14 is caused to move radially inwardly toward the shaft 10. On the other hand, when the follower pin 14 is caused to move radially outwardly, the blades 7 and 8 are caused to turn in a different direction so as to increase the effective size of the light-admitting aperture 6 and to thus prolong the interval during which the aperture allows scene light to reach the window 25 during each revolution of the disk 5 and blades 7 and 8.-The adjusting mechanism for the blades 7 and 8 further comprises two displacing elements in the form of cams 17 and 18 which are located at the opposite sides of the path along which the follower pin 14 orbits about the axis of the shaft.l0 when the motor of the camera rotates the drive shaft 12. The displacing elements or cams 17 and 18 are mounted on an arm ofa shifter 21 which is reciprocable in the body of the motion picture camera. To this end, the shifter 21 is provided with two longitudinally spaced elongated slots 20 for pins 19 which are mounted in the camera body. This shifter is preferably provided with a handgrip portion (not shown) which can be grasped by two fingers to effect a movement of the shifter either in an upward direction or in a downward direction, as viewed in FIG. I.

The operation of the improved shutter is as follows:

It is assumed that the disk 5 and the blades 7, 8 are rotated by the pinion 11 in a clockwise direction, as

viewed in FIG. I. If the user of thecamera wishes to reduce the effective size of the aperture 6, the shifter 21 is moved downwardly whereby the displacing element or cam 18 moves into the path of orbital movement of the follower pin 14 and causes the pin to move radially inwardly towards the axis of the shaft 10. The shifter 21 is preferably movable in stepwise fashion so that the effective size of the aperture 6 is reduced gradually. This is particularly desirable when the user of the camera wishes to make effect shots of the type known as fadeout. It the user wishes to gradually increase the effective size of the aperture 6, the shifter 21 is moved stepwise in an upward direction, as viewed in FIG. 1, whereby the displacing element or cam 17 moves into the path of the orbiting follower pin 14 and causes the latter to move along the slot 13b and radially outwardly away from the axis of the shaft 10. The follower pin 14 thereby travels along the slot 13)) as well as along the cam slots 15 and I6 and causes simultaneous turning of the blades 7 and 8 relative to the disk 5. As mentioned before, the shifter 21 can be moved up or down, as viewed in FIG. 1, in stepwise fashion. To facilitate such stepwise movements of the shifter 21, the camera body can be provided with a suitable scale having graduations which are indicative of different positions of the shifter 21 and of different effective sizes of the aperture 6. The arrangement may be such that the shifter 21 is moved once during each revolution of the disk 5 so that each of a series of successive exposures is made with a light-admitting aperture 6 of different effective size. The frictional engagement between the follower pin 14 and the surfaces flanking the radial slot 13b of the guide member 13 insures that the follower pin cannot move excepting when engaged by one of the displacing elements 17, 18.

It will be noted that the parts of the improved shutter occupy very little room as considered in the direction of the axis of the shaft 10. This is particularly important in miniature motion picture cameras whose body is preferably dimensioned in such a way that the entire camera can be readily inserted into a pocket. Furthermore, since the shutter occupies so little room, the miniature camera which embodies the shutter can be further equipped with a fully or partially automatic fading mechanism which enables the user to make effect shots know as exposures with fade-out and fade-in effect. Such fading mechanism may comprise a programing wheel(not shown) which rotates through 360 during the making of a complete series of exposures with fadeout and fade-in effect. For example, the programming wheel can be coupled with the shifter 21 by means of a member 22 which is shown in FIG. 1 in such a way that, during a first part of a full revolution of the programming wheel, the shifter 21 will cause the blades 7 and 8 to gradually reduce the effective size of the aperture 6 to zero whereby the camera makes a series of exposures with fade-out effect. During the next stage of the same revolution of the programming wheel, the member 22 causes the shifter 21 to remain at a standstill'while the programing wheel causes the motor to transport the film rearwardly so as to move rearwardly all such film frames which were exposed with fade-out effect. During the last stage of the same revolution of the programming wheel, the member 22 causes the shifter 21 to turn the blades 7 and 8 in such directions that the effective size of the light-admitting aperture 6 is gradually reduced from zero to a maximum value so that the camera makes a series of exposures with fadein effect. The exposures with fade-in effect are superimposed upon the exposures with fade-out effect so that the observer of the film, while the film is being transported through a motion picture projector, gains the impression that the last part of a preceeding scene merges into the foremost part of the next-following scene. The operative connection between the justdiscussed programing wheel and the member 22 which can move the shifter 21 relative to the stationary guide pins 19 may comprise a disk-shaped cam which moves the adjusting member 22 in stepwise fashion during the first and third stages of a full revolution of the programing wheel.

The compactness of the improved adjustable rotary shutter is attributable to the fact that the component parts of the adjusting means for the blades 7 and 8 are movable radially rather than axially of the shutter. It will be noted that the shifter 21 and the follower pin 14 as well as the displacing elements 17 and 18 are mounted for movement radially of the shaft 10. Therefore, the component parts of the shutter occupy little room as considered in the direction of the common axis of rotation of the members 5, 7 and 8. The displacing elements 17 and i8 occupy very little room because they do not have to extend circumferentially around the entire sleeve 9. As shown in FIG. 1, the length of the followenengaging surfaces of the displacing elements l7 and 18 is extremely short. Nevertheless, these elements can readily move the follower pin 14 radially of the shaft 10 while the disk 5 rotates in response to rotation of the drive shaft 12.

It is clear that the improved shutter is susceptable of various modifications without departing from the spirit of the invention. For example, the follower pin 14 can be coupled to a single blade or to three or more blades. Furthermore, the follower pin can be mounted on one of the blades 7, 8 and the cam slot for such follower pin can be provided in the disk 5. Still further, the follower pin 14 can be received in the guide slot 13b with a certain amount of play if the shutter comprises other means for preventing uncontrolled radial movements of the follower pin 14 in response to impact against the displacing element 17 or 18 while the parts 5, 7 and 8 rotate.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features which fairly constitute essential characteristics of the generic and specific aspects of my contribution to the art and, therefore, such adapatations should and are intended to be comprehended within the meaning and range of equivalence of the claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended 1. An adjustable shutter, particularly for motion picture cameras, comprising a housing; a shaft rotatably mounted in said housing; drive means for rotating said shaft; a first rotary member mounted on and arranged to rotate with said shaft and having a light-admitting aperture; at least one second member mounted on and the effective size of said aperture; and adjusting means for moving said one member relative to said other member, including follower means supported by and rotatable with one of said first and second members, cam means provided on and rotatable with the other of said first and second members, said follower means being movable radially relativeto said shaft along said cam means to thereby move said movable member angularly, and displacing means mounted in said housing and being actuatable to move said follower means radially of said shaft.

2. A shutter as defined in claim 1, wherein said first member is provided with guide means for said follower means and said cam means is provided on said second member.

3. A shutter as defined in claim 2, wherein said cam means is an arcuate cam having portions located at different distances from said shaft so that, when said follower means is moved radially of said shaft, said movable member turns relative to the other member.

4. A shutter as defined in claim 1, further comprising guide means provided on that one of said members which supports said follower means, said follower means being in frictional engagement with and being movable relative to said guide means.

5. A shutter as defined in claim 4, wherein said guide means is a spring secured to said first member, said second member being movable angularly relative to said first member in response to movement of said follower means relative to said guide means.

6. A shutter as defined in claim I, wherein said displacing means comprises a first displacing element which is actuatable to move said follower means toward said shaft and a second displacing element which is actuatable to move said follower means away from said shaft.

7. A shutter as defined in claim 6, further comprising common shifter means for said displacing elements.

8. A shutter as defined in claim 7, wherein said shifter means is reciprocable along a straight path.

9. A shutter as defined in claim 1, further comprising means for actuating said displacing means in accordance with a predetermined program.

10. A shutter as defined in claim 2, wherein said follower means orbit about said shaft when said shaft is rotated by said drive means, said displacing means being arranged to move into the path of orbital movement of said follower means to thereby move said follower means along said cam means while said members rotate with said shaft.

11. A shutter as defined in claim 1, further comprising shifter means movably mounted on said housing and arranged to actuate said displacing means stepwise so as to effect gradual changes in the effective size of said aperture. 

1. An adjustable shutter, particularly for motion picture cameras, comprising a housing; a shaft rotatably mounted in said housing; drive means for rotating said shaft; a first rotary member mounted on and arranged to rotate with said shaft and having a light-admitting aperture; at least one second member mounted on and arranged to rotate with said shaft, one of said members being movable angularly relative to the other member to thereby cause said second member to overlie varying portions of said aperture with corresponding changes in the effective size of said aperture; and adjusting means for moving said one member relative to said other member, including follower means supported by and rotatable with one of said first and second members, cam means provided on and rotatable with the other of said first and second members, said follower means being movable radially relative to said shaft along said cam means to thereby move said movable member angularly, and displacing means mounted in said housing and being actuatable to move said follower means radially of said shaft.
 2. A shutter as defined in claim 1, wherein said first member is provided with guide means for said follower means and said cam means is provided on said second member.
 3. A shutter as defined in claim 2, wherein said cam means is an arcuate cam having portions located at different distances from said shaft so that, when said follower means is moved radially of said shaft, said movable member turns relative to the other member.
 4. A shutter as defined in claim 1, further comprising guide means provided on that one of said members which supports said follower means, said follower means being in frictional engagement with and being movable relative to said guide means.
 5. A shutter as defined in claim 4, wherein said guide means is a spring secured to said first member, said second member being movable angularly relative to said first member in response to movement of said follower means relative to said guide means.
 6. A shutter as defined in claim 1, wherein said displacing means comprises a first displacing element which is actuatable to move said follower means toward said shaft and a second displacing element which is actuatable to move said follower meanS away from said shaft.
 7. A shutter as defined in claim 6, further comprising common shifter means for said displacing elements.
 8. A shutter as defined in claim 7, wherein said shifter means is reciprocable along a straight path.
 9. A shutter as defined in claim 1, further comprising means for actuating said displacing means in accordance with a predetermined program.
 10. A shutter as defined in claim 2, wherein said follower means orbit about said shaft when said shaft is rotated by said drive means, said displacing means being arranged to move into the path of orbital movement of said follower means to thereby move said follower means along said cam means while said members rotate with said shaft.
 11. A shutter as defined in claim 1, further comprising shifter means movably mounted on said housing and arranged to actuate said displacing means stepwise so as to effect gradual changes in the effective size of said aperture. 